[RFC PATCH v4 15/18] kvm: x86: hook in kvmi_xsetbv_event()

[Adalber Lazăr <alazar@xxxxxxxxxxxxxxx>]

From: Adalbert Lazar <alazar@xxxxxxxxxxxxxxx>

Notify the guest introspection tool that the extended control register
has been changed.

Signed-off-by: Mihai Donțu <mdontu@xxxxxxxxxxxxxxx>
---
 arch/x86/kvm/x86.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8f5cc81c8760..284bb4c740fa 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -765,6 +765,9 @@ static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr)
 
 int kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr)
 {
+	if (xcr != vcpu->arch.xcr0)
+		kvmi_xsetbv_event(vcpu);
+
 	if (kvm_x86_ops->get_cpl(vcpu) != 0 ||
 	    __kvm_set_xcr(vcpu, index, xcr)) {
 		kvm_inject_gp(vcpu, 0);